Dynamic analysis of self-supported tower under hurricane wind conditions

Abstract

Self-supported telecommunication towers are very important structures in the infrastructure of countries. These structures are highly sensitive to the dynamic effects of wind loads. Several self-supported telecommunication towers have collapsed in Cuba during the last decades due to strong hurricane winds, causing important economic and social losses. The aim of this work is to compare the structural response of a self-supported tower in terms of internal forces and displacements by static equivalent and full dynamic time history methods, taking into account hurricane wind conditions. The static equivalent method used in this paper was Gust Response Factor with the formulation proposed in Eurocode EC 3: Part 3-1. Time history analysis was performed using generated simulated wind data obtained through Montecarlo’s technique and the turbulent component of the velocity was obtained by the formula presented by Shinozuka and Jan. Turbulence parameters, such as power spectral density function, integral scale and turbulence variance were assumed in accordance with the international literature on structural monitoring subjected to hurricane action. A 60m high lattice tower having a square in-plane cross-section was studied. Forces on members and displacements on the tower were found to be 20–25% higher when applying the static equivalent method, as compared to time history method.